let isovist = [];

​

function preload(){

  floorplan = loadImage("floorplan.jpg");

}

​

function setup() {

  createCanvas(floorplan.width, floorplan.height);

}

​

function draw() {

  // image(floorplan,0,0)

  background(0);

  // fill("red")

  // noStroke();

  beginShape();

  for(let i = 1; i< isovist.length; i++){

    vertex(isovist[i].x, isovist[i].y)

  }

  endShape(CLOSE);

  noFill();

  stroke("red")

  // strokeWeight(2);

  // for(let i = 1; i< isovist.length; i++){

  //  line(isovist[0].x, isovist[0].y,

  //      isovist[i].x, isovist[i].y)

  // }

}

​

function mouseMoved(){

  isovist = [createVector(mouseX,mouseY)];

  for(let alph = 0; alph<2*PI; alph+=0.05){

    let walls = 0;

    let coord = createVector(mouseX, mouseY);

    let length = 0;

    while(walls < 6 

          && coord.x>0 && coord.x< width 

          && coord.y>0 && coord.y< height){

      if(floorplan.get(coord.x, coord.y)[0] < 100){

        walls++;

        }

      else{walls=0}

      length++;

      coord = createVector( mouseX + cos(alph) * length,

                           mouseY + sin(alph) * length)

      }

    isovist.push(coord);

  }

}